1. Field of the Invention
The present invention relates to an image forming apparatus utilizing an electric field formed in an opening, particularly relates to controlling the passing of charged particles such as ions or developer particles, for example charged toner particles or charged ink droplets (hereinafter collectively called toner), through said opening, and more particularly relates to the cleaning of the means for controlling the passing of such charged particles.
2. Description of the Prior Art
A direct recording process for image formation on an image receiving member by modulation of toner is disclosed in the U.S. Pat. No. 3,689,935. Said process utilizes a toner control member composed of two electrodes positioned across an insulating layer and provided with linearly arranged openings, through which the charged toner particles are supplied under control from a toner supply source, thereby forming an image on a recording member placed across said toner control member. The above-mentioned process is, however, not adequate for practical use because of drawbacks such as the uneven toner supply leading to uneven image formation on the recording member, difficulty in high-speed recording and clogging of the openings of the control member with toner.